Log Message:

Update to version 0.19.0
  fix in runawk.c: \n was missed in "running '%s' failed: %s" error
  message.  The problem was seen on ancient (12 years old) HP-UX

  fix in teets/test.mk: "diff -u" is not portable (SunOS, HP-UX),
  DIFF_PROG variable is introduced to fix the problem

  fix in modules/power_getopt.awk: after printing help message we
  should exit immediately not running END section, s/exit/exitnow/

  new function heapsort_values in heapsort.awk module

  new function quicksort_values in quicksort.awk module

  new function sort_values in sort.awk module